This invention relates to a disc cartridge, and more particularly to a disc cartridge which has a hard disc, particularly, a double-sided type hard disc housed in a casing.
In general, a disc-type data recording carrier such as a compact disc (CD), a video disc (LD) or the like is used in a manner to be removed from a packing case and set in a recording and/or reproducing equipment such as a disc player.
Conventionally, it has been desirable to protect such a disc type recording carrier from environment because it is not only readily covered with dust and damaged but adversely affected due to a variation in temperature. For this purpose, the use of an envelope such as a tray, a casing or the like has been proposed to protect the disc. Unfortunately, such a conventional envelope is not effective to protect a double-sided hard disc, because the housing of the disc in a storage space defined in the envelope causes the disc, particularly, a recording surface section of the disc to be contacted by an inner surface of the envelope. Such contacting also takes place during storage or transportation of the envelope. Thus, the use of the envelope still results in damage and/or pollution of the disc as well as the exposure of the disc to a variation in temperature.
Also, an envelope in which a hard disc is housed has a sliding member such as a shutter or the like mounted thereon and must be provided therein with an internal space sufficient to receive the hard disc therein, so that a wall thickness of the envelope is substantially decreased to a degree sufficient to deteriorate its rigidity. This often results in the sliding member failing to exhibit its satisfactory function. In particular, the envelope is often distorted or deformed due to external force applied thereto, pressing or the like, so that the internal space of the envelope is reduced to cause function of the sliding member to be deteriorated and a disc receiver to fail in pivotal movement. Further, the distortion and/or deformation of the envelope causes the disc to be contacted with an inner surface of the envelope to deteriorate its function.
Accordingly, it would be highly desirable to provide a disc cartridge which is capable of positively ensuring smooth movement of a sliding member and a disc receiver irrespective of distortion and/or deformation of a casing due to external force, pressing or the like, as well as safely housing a disc in the casing without contacting the casing.